Upblast Centrifugal Roof Exhaust
7
Pre-Starting Checks
1. Check all fasteners and setscrews for tightness.
The wheel should rotate freely and be aligned as
shown in Figure 12.
2. Wheel position is preset and the unit is test run at
the factory. Movement may occur during shipment
and realignment may be necessary.
Centering the wheel can be accomplished by
loosening the bolts on the support pan and moving
support pan until wheel is properly aligned. For
units with drive frame mounting, loosen the bolts
holding the drive frame to the vibration isolators
and reposition the drive frame if additional
movement is needed for wheel alignment.
Wheel and inlet cone overlap can be adjusted
by loosening the setscrews in the wheel hub and
moving the wheel to the desired position. For
direct and belt drive models with wheel hubs and
shaft pulleys utilizing tapered bushing interface,
reference page 9 for tapered bushing removal and
move the wheel to the desired position.
3. Check wheel rotation (viewing from the shaft side)
by momentarily energizing the unit. Rotation should
be clockwise as shown in
Figure 13 and correspond to
the rotation decal on the unit.
If wheel rotation is incorrect,
reverse two of the wiring leads
or check motor wiring for
single phase. Fan RPM should
be checked and verified with a
tachometer.
Figure 12
Wheel Overlap and Gap Dimension
G
H
Model Type
Model
Size
G - Overlap
inch
(mm)
H - Gap
inch
(mm)
Direct
Belt
X
–
060-095
–
3/32
(2)
X
X
099-161
1/4
(6)
–
X
X
180-300
1/2
(13)
–
–
X
360-480
3/4
(19)
–
Figure 13
WARNING
Correct direction of wheel rotation is critical. Reversed
rotation will result in poor air performance, motor
overloading and possible motor burnout.
AVERTISSEMENT
La turbine doit impérativement tourner dans le bon
sens. Une rotation en sens inverse entraînerait de
mauvaises performances de soufflage, une surcharge
du moteur voire un grillage du moteur.
CORRECT
WRONG
WRONG
WRONG
Figure 15
Belt Drive Pre-Starting Belt Tension Checks
4. Always loosen tension
enough to install belts
without stretching.
Do not force belt(s)
see
Figure 14. Forcing belts
will break the cords and cause belt failure.
5. For units with two groove pulleys, adjust so the
tension is equal in both belts.
6. If adjustments are made, it is very important to
check the pulleys for proper alignment. Misaligned
pulleys lead to excessive belt wear, vibration, noise
and power loss, see Figure 15.
Figure 14
High Wind Ratings
Seismic Ratings
Fasteners
Fasteners
Fan
Size
Curb Cap Size
inches
(millimeters)
Per
Side
Total
Fan Size
Per
Side
Total
Steel
≤
161
17x17 to 22x22
(432x432 to 559x559 mm)
3
12
060-240
2
8
>
161
26x26 to 40x40
(660x660 to 1016x1016 mm)
4
16
300-360
3
12
420-480
5
20
Concr
ete
≤
161
17x17 to 22x22
(432x432 to 559x559 mm)
3
12
060-240
2
8
>
161
26x26 to 40x40
(660x660 to 1016x1016 mm)
3
12
300-360
3
12
420-480
5
20
W
ood
≤
161
17x17 to 22x22
(432x432 to 559x559 mm)
3
12
060-240
2
8
>
161
26x26 to 40x40
(660x660 to 1016x1016 mm)
4
16
300-360
3
12
420-480
5
20
All dimensions are in inches
(millimeters)
.
Curb to Deck Mounting:
Fasteners need to be located
on all four sides of the curb, Figures 11a and 11b.
Roof Curb
Roof Curb
3/8 in.
(10 mm)
S.S. Hilti Kwik Bolt 3
Expansion Anchors
Min. 2-1/2 in.
(64mm)
Engagement
1/4 in. - 14 Self-Drilling Screw Min.
1/2 in.
(13 mm)
of Threads Through
3000 Min. PSI
Concrete
Concrete Anchoring
Steel Anchoring
Roof Truss
1/8 in.
(3 mm)
Thick or 12 ga. Min.
Roof Curb
Timber Anchoring
Wood Timber
Min. 4 in. (102 mm)
Nominal Thickness
Min. G=0.42
G = specific gravity
of lumber
3/8 in.
(10 mm)
Lag Bolt (Zinc Plated)
Min. 3 in.
(76 mm)
Thread Engagement
Figure 11a
Figure 11b
